Back up storage spaces and logical-log files

When you use HDR, you must back up logical-log files and
storage spaces only on the primary database server. Be prepared, however,
to perform storage-space and logical-log backups on the secondary
database server in case the type of the database server is changed
to standard.

You must use the same backup and restore tool on both
database servers.

The block size and tape size used (for both
storage-space backups and logical-log backups) must be identical on
the primary and secondary database servers.

You can use ontape to
set the tape size to 0 to automatically use the full
physical capacity of a tape.